Wire a Mono layer into this node to adjust where the smoke emits from. This node controls the thickness of the fire emission. A value of 0 will have no fire and 1 will have the full thickness. Note that the input is animated to create a pulse of explosion for a few frames.

Adjusts the resolution of the fireball. This is the number of voxels across the default imaging window. Higher resolutions will take considerably more time and memory.

The VDB has to be activated so you can source into it. Layer to VDB Leaf Points handles the activation from the SOURCE layer, while the Pyro Source from Layer handles the actual sourcing. The thickness and inputs for these two nodes should match.

The start of the simulation loop. All nodes inside the convex hull (highlighted area) will run every simulation step. The simulation is clipped from -1 to 1 by default, and can be controlled by modifying the Clip X/Y/Z parameters.

The hot areas of the simulation are set to expand. This node remaps the temperature field into how much divergence to apply. It ensures no expansion occurs below a minimal temperature of 0.1 and that a temperature of 1 would trigger 8 units of divergence. Too little divergence and there is no apparent effect, too much and the simulation rapidly explodes.

Computes internal scattering of light within the fireball’s smoke. This takes the glow of temperature and diffuses it by bouncing it internally through the density field. This is most effective at creating an internal glow look to dark smoke.

Computes lighting for the fire’s smoke using an ambient light source. Increasing smoke density (with the Density Scale parameter) increases the contrast of self-shadows.

Renders the fireball into a layer. The camera_ref can use an imported camera from the Camera Import COP to change the view or resolution of the render.